Racial disparities in health status, and in particular the excess rates of hypertension (HT) among Blacks, are widely recognized. Investigators have hypothesized that social stressors, including exposure to racism or ethnic discrimination, may contribute to increased risk for HT and cardiovascular disease (CVD). The specific aim of the proposed study is to test a model of the relationships among ethnic discrimination, coping, and ambulatory blood pressure (ABP). The model proposes that perceived exposure to ethnic discrimination will be positively associated with the average level of ABP and with the magnitude and duration of acute blood pressure and heart rate responses to current negative interpersonal interactions. Coping styles and strategies used to manage ethnic discrimination are expected to mediate the relationship of ethnic discrimination to ABP. Socioeconomic status (SES) is expected to moderate the relationship of racism to coping and the relationships of ethnic discrimination and coping to ABP. To test the generalizability of this model, the hypotheses will be tested in a multi-site sample of 720 American-born Black and Latino men and women drawn from urban primary care medical practices. These practices are located in culturally diverse communities, serving patients from a range of socioeconomic backgrounds. Participants will wear an ambulatory blood pressure monitor for 24 hours. Questionnaires will be used to assess past exposure to ethnic/racial discrimination. Diaries completed at the time of each ambulatory blood pressure reading will be used to identify day-of-testing negative and potentially discriminatory interactions. Both characteristic styles of coping and episode-specific strategies for coping with ethnic discrimination are examined. Demographic and personality variables likely to affect perceptions of ethnic discrimination will be examined and controlled. Structural equation modeling will be employed to evaluate the relationships among perceived ethnic discrimination to coping and ABP. Additional analyses will examine the association of gender, SES, and race/ethnicity to the use of different styles and strategies for coping with ethnic discrimination, and the effects of these characteristics on the relationship of coping to ABP. The study has implications for theories concerning the relationship of psychosocial stress to risk for HT and for the development of interventions to reduce racial disparities in health status.